Anderson was a Democratic activist and an aide to Seattle City Council Member George Benson and to Mayor Charles Royer. He was a decorated combat veteran of the U.S. Army in Vietnam and called himself, "a Democrat who happens to be gay" (The Seattle Times). In the legislature Anderson backed gay rights legislation and battled initiatives that would discriminate against gays. He also worked for campaign finance reform, easier voter registration, and open access to government documents.
Cal Anderson died on August 4, 1995, of an illness related to Acquired Immunodeficiency Syndrome (AIDS). On April 19, 2003, Cal Anderson Park, on Seattle's Capitol Hill, was named and dedicated in his honor, along with the park's new structure, the Cal Anderson Shelterhouse. On September 24, 2005, the community celebrated the grand re-opening of the park.